Steps to Install:
-Extract .PNG from the RAR
-Open SparkIV OR OpenIV
-Go to GTA IV Directory/pc/cdimages/vehicles
-Find the required car you wish to apply the PJ to
-Click 'EDIT MODE' on
-Open the .WTD file
-Find the slot you wish to replace
-It should look similar to: xxx_sign_1/xxx_sign_2 etc. etc.

Haven't uploaded a PJ in a while, but I'm not gone. Hope you guys enjoy this.
Oh and I'm into converting cars now, so check out my releases over at GTAMAD :)